Grok 4 Fast Non-Reasoning API

x-ai/grok-4-fast-non-reasoning
Grok 4 Fast Non-Reasoning specializes in rapid, deterministic text-to-text generation without advanced reasoning or tool use.
Context
2M tokens
Input
$1.625 / 1M tokens
Output
$3.25 / 1M tokens
Released
Sep 30, 2025

How to use Grok 4 Fast Non-Reasoning API

Install any OpenAI-compatible SDK, point it at api.aimlapi.com/v1, and set the model to x-ai/grok-4-fast-non-reasoning.
import requests

r = requests.post(
    "https://api.aimlapi.com/v1/chat/completions",
    headers={"Authorization": "Bearer " + AIMLAPI_KEY},
    json={
      "model": "x-ai/grok-4-fast-non-reasoning",
      "messages": [
        {
          "role": "user",
          "content": "Hello!"
        }
      ]
    },
)
print(r.json())
const r = await fetch("https://api.aimlapi.com/v1/chat/completions", {
  method: "POST",
  headers: {
    Authorization: `Bearer ${process.env.AIMLAPI_KEY}`,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    "model": "x-ai/grok-4-fast-non-reasoning",
    "messages": [
      {
        "role": "user",
        "content": "Hello!"
      }
    ]
  }),
});
console.log(await r.json());
curl -X POST https://api.aimlapi.com/v1/chat/completions \
  -H "Authorization: Bearer $AIMLAPI_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model":"x-ai/grok-4-fast-non-reasoning","messages":[{"role":"user","content":"Hello!"}]}'

OpenAI-compatible — swap the base URL and it works with your existing SDK.

Grok 4 Fast Non-Reasoning API Pricing

TypePrice
Input
$1.625 / 1M tokens
Output
$3.25 / 1M tokens
Cached input
$0.26 / 1M tokens

Grok 4 Fast Non-Reasoning Benchmarks

BenchmarkScoreWhat it measuresSourceRetrieved
Intelligence
17.9
Composite score across standardised reasoning, knowledge and problem-solving evaluations, measured independently by Artificial AnalysisSourceSeptember 12, 2026
Math
89.7
Composite score across standardised mathematics evaluations, measured independently by Artificial AnalysisSourceSeptember 12, 2026

Grok 4 Fast Non-Reasoning vs other models

ModelInputOutputContextBest for
$1.625 / 1M tokens
$3.25 / 1M tokens
2M tokens
Coding + agents
$6.5 / 1M tokens
$39 / 1M tokens
1M tokens
Reasoning + agents
$2.6 / 1M tokens
$13 / 1M tokens
1M tokens
Balanced coding + agents
$3.9 / 1M tokens
$19.5 / 1M tokens
1M tokens
Long-context, multimodal & agentic workflows
$1.95 / 1M tokens
$11.7 / 1M tokens
1M tokens
Reasoning + agents

Frequently asked questions

Grok 4 Fast Non-Reasoning has a 2,000,000 tokens context window and can return up to 1,999,000 tokens.

Grok 4 Fast Non-Reasoning takes image, text as input and returns text.

Use x-ai/grok-4-fast-non-reasoning as the model id. Requests go to https://api.aimlapi.com/v1/chat/completions.

Grok 4 Fast Non-Reasoning is priced at input $1.625 / 1M tokens, output $3.25 / 1M tokens, cached input $0.26 / 1M tokens.

Yes, Grok 4 Fast Non-Reasoning can stream responses as they are generated.

Yes, Grok 4 Fast Non-Reasoning accepts image input alongside text.

Grok 4 Fast Non-Reasoning was built by xAI .

It is built to give faster responses with lower latency by skipping the reasoning step.

Yes, it supports function calling, parallel tool calls, and tool use, though it does not perform extended reasoning.

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